A certain style of familiar American chimney which is made of laid up brick, stone or cement block is commonly lined with stacked-up fired clay tiles. The tiles protect the joints of the masonry and provide a smooth upward convective path for products of combustion from such as a fireplace or a heating system in a building. In typical construction, the tiles fit closely the bore of the masonry chimney and have tight-fit horizontal joints. See FIG. 1 of this application.
Chimney tiles may need to be replaced from time to time because they fracture during use or during cleaning of the chimney. In another circumstance, a building owner may want to install a metal liner, such as a round stainless steel conduit, within the chimney for the improvement which such provides. To accomplish that, it is ordinarily desirable to remove the ceramic tiles so a sufficiently large diameter of metal liner can be installed. The present invention facilitates the removal of tiles for such purposes.
While the uppermost tiles might be manually grasped and lifted from the top of the chimney, those which are further from the top have heretofore most often be removed by fracturing each tile into smaller pieces. A worker standing at the chimney top may use a weighted flail or rotating weight inserted into the bore of the chimney. The broken pieces of tile will fall along with other debris to the bottom of the chimney. That can create a mess or a removal problem when the chimney does not terminate in a fireplace. Misuse of the tile-breaker may damage chimney bricks. The patent literature describes prior art tools and methods that relate to the need to remove tiles, as exemplified by the following.
Golden U.S. Pat. No. 4,603,747 shows a motor driven rotary impact hammer which is suspended within a chimney from a vertical cable. The hammer fractures tiles so they fall to the bottom of the chimney.
Scherdinger U.S. Pat. No. 2,794,669 shows a cable-suspended chimney tile grasping device having shoes which move outwardly to frictionally engage the bore of a tile which can then be lifted or lowered within a chimney bore. In one embodiment, the tool is lowered while locked in a first compact configuration. The locking mechanism is then released by pulling on a line and opposing-side shoes to move laterally to engage the bore of a tile. When the tool is pulled upwardly by a lifting line the arms and levers in the device cause the shoes to exert increased lateral force against the tile interior.
Bruckelmyer U.S. Pat. No. 5,881,420 shows device, which comprises a horizontal debris-catching plate, for use when a chimney is being brush-cleaned. The device is lowered by means of a vertical rod and fixedly positioned within the flue of the chimney. When the vertical rod is twisted, a scissors mechanism causes opposing pads to expand horizontally within the bore of the chimney to frictionally grip the bore. While the patent mentions replacing tiles, the only function of the tool is to catch debris.
Yakushinji U.S. Pat. No. 6,254,157 and shows a device for lifting loads, such as concrete blocks. When pulled vertically, a compound link mechanism causes closure of the grip ends of scissor-arms. Similarly, Helms U.S. Pat. Publication No. 2004/0135389 shows a lifting mechanism for plates. Opposing side arms having flat-plate grips squeeze together horizontally with scissor like action to grab a manhole cover. Upward pulling-force causes the squeezing action.
Wolford U.S. Pat. No. 8,454,065 shows devices for lifting articles like hollow concrete blocks. In particular at FIG. 3 a scissor-arm device is shown. The device has parallel jaws which grab the vertical wall or web of a hollow concrete block. The jaws are at the ends of arms which move together as a result of the vertical lifting force transmitted to the arms by a link mechanism.
The prior art devices do not sufficiently serve the needs of persons working to remove chimney tiles in a quick and effective manner. Those prior art devices which frictionally clamp the bore will not work effectively on tiles which are vertically fractured. Those prior art devices which clamp on the exterior of an object, or onto the vertical web of a hollow object like a tile, are ill-suited to grab the edge of a tile which lying in close proximity to the masonry bore of a chimney. And once a tile is grasped there is a further need: The tile must be lifted in a way which avoids cocking and jamming within the bore of the chimney. Furthermore, since a chimney repair person is often working high on a roof in a hazardous location, possibly in sub-optimal weather conditions, any tool should be easy to use, and preferably light in weight. Of course a tool should be sturdy and easily maintained.